Airplane control surfaces



"r, N. JOYCE AIRPLANE CONTROL SURFACES I March 26; 1940.

Filed July 20, 1938 Patented Mar. 1940 UNITED STATES j PATENT OFFICE f v2,194,796 AIRPLANE CONTROL SURFACES 'l'empleN. Joyce, Arnold, Md.,assignor to Zap Development Corporation, Baltimore, Md., a corporationof Delaware Application July: 20, 1938, Serial No. 2201360 3 Claims,(01. 244-42) This invention relates to airplanes and more particularlyto control suriaces for airplanes.

The present invention is generally similar to that covered in myco-pending application 220,359

filed concurrently herewith but includes additional important features.

An object of the present invention is to'pro-'- vide a flap and aileronconstruction in which the flap can extend substantially the full lengthof m the airplane wing.

Another object of my inventionis to provide an airplane wing that willhave proper lateral control when the plane is flying at either high orlow speeds. I

Yet a further object 0! my invention is the provision of a flap andaileron combination that will form the trailing edge of the wing.

Yet another object of my invention is the provision or spoiler, flap andaileron surfaces so associated that the aileron cannot be operated aslong as the flap is in its inoperative position.

. To accomplish the above and additional objects, this inventioncomprehends the employment of a wing having spoiler, flap and aileronsurfaces that are so associated that'when the airplane is flying at highspeeds, the flap and aileron are in their'inoperative' positions. Due

to the manner in which these surfaces arec'onnected, it is not possibleto actuate the aileron so as long as the flap is in its inoperativeposition. The spoilers, however, are free to be operated at high speeds,thereby giving the necessary lateral control for theairplane.

When the airplane is flyin at low speed and the flap is lowered by thepilot, means are pro-. vided whereby the aileron can be operated.

In order to readily comprehend my invention, attention is directed tothe ,accompanying drawing which illustrates the preferred embodiment 0of my inventive concept, it being understood, however, that numerouschanges may be made by those skilled in the art without exceeding thescope of the invention as described by the annexed claims. a

In the drawing in which like numerals designate similar parts: v

Figure 1 is 'a view in side elevation,. partly in section, 01 anairplane wing depicting my invention.

Figure 2 is a iragmentalsectional view of the.

trailing edge of the wing-shown 'in Figure 1 illustrating the flap inits lowered position and the aileron free to be actuated.

Flgure3 isaviewtaken along line l3 of 5 Figure 1 looking lathe directionor the arrows.

Referring particularly to Figure 1, there is shown an airplane wing Ihaving a front spar I and a rear spar 3. The wing is provided with aflap l and an aileron 5 which, it will be noted. form the trailing edgeof the wing I. 5

' A spoiler 8 which is hinged to the upper leading edge of the wing I asshown at i is adapted to fit within a, well 8.-when the spoiler is inits inoperativeposition. Of course, it is to be understood thatthespo'iler can-be disposed at any 10 location-on the upper area oi.thewing, or it. plurality oi spoilers can be used.

To move the spoiler about its pivot 1, it can be seen that a bell crank9 ispivotally mounted at Ill to a support II secured to the front spar2, '15 A link I! is attached at one end to the bell crank and at itsopposite end to the undersurface of the spoiler t; The other arm oi thebell crank 9 is attached to an operating-cable ill by a pivotalconnection It. A coil spring II, one end of which a any desired mannerwith the pilot's controls (not shown).

As shown in Figure 2, the flap I is provided with upstanding supports itin which is journalled a stub shaft II. A link It is attached to theshaft n and the outer end is fixed by pivoting to a tube 19 extendingthrough the leading edge of the aileron B.

It can be noted that a pair-oi the braces for the interior oi" the wingare provided with elongated slots 2|.

rollers 22 that ride in the slots 20.

An operating link 23 is-attached to the shaft TH and extends through anaperture 24 in the rear spar t. The oppodte end or the-link 23 is 5pivotally attached as shown at 25 to operating arms 2} that are in turnsecured to a torque tube 21 journalled in the Wing's interior bracingmembers.

' A control rod 28 that extends toa position 50 convenient for the pilotis pivotally attached to asleeve Itseouredto thetorquetube'TL,

It will be readily apparent to those skilled in the art that when theflap 4 is inthe position shown. in Figure 1 it is not possible to lowerthe as A shaft 2i that extends through 40 apertures in the supports itof the flap I carries aileron 5. However, the spoilers l are free to beoperated andprovlde tor the necessary lateral control.

when it is desired to lower the flap 4, it will be appreciated that byactuating the control rod 28, the torque tube 21 will be rotated and thearms 26 will move through an are forcing the link 23 rearwardly andcausing the rollers 22 to ride in the slot 20 moving the flap to theposition shown in Figure 2. While I have shown the I control forairplanes that will be highly eflective under all conditions of flight.By having the aileron 5 and the flap 4 connected in the manner shown,the aileron cannot be moved to its operative position as long as theflap is in its inoperative position.

The spoilers 6, however, are free to be operated when the flap andaileron are in their inopera-' tive positions. By employing the spoilersurfaces 6 to afford lateral control at high speeds, parasitic drag ismaterially reduced.

On the other hand, when the plane is flying at a low speed and the flapis lowered, the'aileron 5 can then be operated by the pilot. The aileronis highly eilective at low speeds inasmuch as it is stimulated by theflow of air over the top surface of the wing by the flap 5.

While I have shown the preferred embodiment of my invention, it is, ofcourse, to be understood that I am not limited to the precise detailsherein set forth but that the scope of my invention is to be determinedby the annexed claims.

I claim:

1. In an airplane, a wing, a flap adapted to be raised and lowered, anaileron adapted to be actuated downwardly, said flap and aileron formingthe trailing edge of the wing, a link pivotally mounted at one end tothe flap and at the opposite end to the aileron, a second link pivotallyattached to the flap at a point forward of the pivot point of the otherlink to the flap, means associated with said second-mentioned link tolower the flap, said flap when raised lying adjacent the aileron so asto prevent downward actuation of the aileron, and means to actuate theaileron when the flap is lowered.

2. In an airplane, a wing, a flap, an aileron, said flap and aileronforming the trailing edge of the wing, a rotatable shaft fixed to theleading portion of th aileron tor swinging the aileron upwardly anddownwardly, means for slidably and pivotally supporting the leadingportion of the flap on the wing, and a link pivoted between said shaftand the flap for guiding the flap for downward swinging thereof, saidflap when raised lying adjacent the aileron so as to prevent downwardswing of the aileron.

3. In an airplane, a wing,.a flap adapted to be raised and lowered, anaileron adapted to be actuated downwardly, a link interconnecting saidflap and aileron for guiding downward swing of the flap independently ofmovement of the aileron,

